Tsonga was beaten 7-6, 2-6, 3-6 by his fellow Frenchman, who currently sits 46 places below him in the world rankings at 56th.

The 32-year-old became a father for the first time with the birth of his son in March and last played prior to today at the Indian Wells Masters earlier that month.

"I would like to congratulate my opponent," Tsonga, who had won his only previous meeting with Mannarino, said.

"He played a really good match.

"He's one of the players who are really giving it their all on the Tour.

"He's improving a lot."

Mannarino will now go on to face the winner of tomorrow's clash between compatriot Lucas Pouille and Italy’s Paolo Lorenzi.

"It is an important victory for me, beating Jo in a big tournament," he said.

"I'm very satisfied with the match.

"I had the right attitude."

Both Pouille and Lorenzi won their first-round matches today with the former beating the United States' Ryan Harrison 6-2, 6-4 and the latter overcoming Spain's Marcel Granollers by the same scoreline.

World number two Novak Djokovic survived a scare against France's Gilles Simon as the Serb battled back in a dramatic deciding set to claim a 6-3, 3-6, 7-5 win.

The 29-year-old, playing in his first clay match of the year after recovering from an injury to his right elbow, was twice a break down in the final set to world number 32 Simon who had the chance to serve for the match. 

But the two-time champion dug deep to triumph in two-and-a-half hours and will meet the winner of tomorrow's match between Russia's Karen Khachanov and Spain's Pablo Carreño Busta in the third round.

Khachanov was a surprise winner over home favourite Nicolas Mahut today, triumphing 6-2, 6-4.

World number one Andy Murray makes his return to the tour tomorrow when the Briton faces Luxembourg's Gilles Muller, a 6-2, 6-2 winner over Spain's Tommy Robredo.

Among the other notable victors today was world number 655 Tommy Haas of Germany as he registered a 6-2, 6-3 win over world number 40 Benoit Paire of France.

Haas, 39, is the oldest player in the draw and competing at the ATP World Tour Masters 1000 tournament for the first time since 2008.

He will now face ninth-seeded Czech Tomáš Berdych, who defeated Russian qualifier Andrey Kuznetsov 4-6, 6-3, 6-4 yesterday, in the second round.

There was also an unexpected first-round victory for Berdych’s compatriot Jiří Veselý, who beat Germany's Mischa Zverev 7-6, 6-3 and will next face third-seeded Swiss Stan Wawrinka.